The perimeter of a square is $16$ units. How long is each side?
Answer: $\text{? }$ The perimeter is the total length of all the sides of the shape added together. $ {\text{?}} + {\text{?}} + {\text{?}} + {\text{?}} = 16\text{ } $ $ {4} + {4} + {4} + {4} = 16\text{ } $ The sides of a square are all the same length, so each side must be $4$ units long.